Let D be the region in the xy-plane in which the series(adsbygoogle = window.adsbygoogle || []).push({});

Sum k=1 to k= infinity (x+2y)^k /k converges. Then the interior of D is: The open region between two parallel lines.

Can someone explain why this is true? You don't need to work out a full blown solution.

What convergence tests are there for series and when should each be used?

Thanks!!

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# Series convergence

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